Severe rhesus iso-immunization successfully treated with apheresis and azathioprine. Report of 2 cases.

Two patients are described in whom previous fetal loss had occurred due to rhesus (Rh) disease. In both patients apheresis was performed from a gestational age of 25 weeks in an attempt to remove excessive antibodies. In addition, production of new antibodies was suppressed by the administration of prednisone and azathioprine. A reduction in the antibody titres was accomplished although this was not reflected by a marked decrease in amniotic fluid bilirubin levels. The patients were delivered at gestational ages of 32 and 33 weeks since fetal lung maturity had then been demonstrated. Both babies were surprisingly little affected by the Rh disease and only one exchange transfusion was necessary for each. Neonatal follow-up for 2 years and 1 year respectively revealed no fetal abnormalities.